1. Field of the Invention
The present invention relates generally to call management using a call routing engine in a communications system, and more specifically, to a call management technique that involves processing by the engine after an initial call connection has been established in the system.
2. Brief Description of Related Prior Art
Systems for managing and routing calls through public and/or private communications networks are known in the art. Conventional automatic call distribution (ACD) systems route calls to agents in telemarketing and service inquiry centers, and provide limited real-time call management and reporting capabilities. A typical ACD system will monitor the status of the agent and, when an incoming call is received, selects the agent to handle a particular service request. Reporting and performance data from the agents are also generated by the ACD.
One particular type of scheme for distributing calls to agents is disclosed in Frauenthal et al., U.S. Pat. No. 4,737,983. According to Frauenthal et al., data representing the present call congestion of each of the ACD systems is accumulated in a database. Using the data in the database, the percentage of calls made to the ACD systems, as a group, is determined. The information is then used to generate call routing information. When a new call is made to the central office, the routing information is queried to determine which of the ACD systems is to receive the call, so as to balance the call traffic load across the ACD systems.
Another call management and distribution scheme is provided in Gechter et al., U.S. Pat. No. 5,036,535. This patent discloses a system for automatically distributing telephone calls placed over a network to one of a plurality of agent stations connected to the network via service interfaces, and providing status messages to the network. Gechter et al.'s disclosed system includes means for receiving the agent status messages and call arrival messages from the network, which means are connected via a network service interface to the network. Routing means responsive to the receiving means is provided for generating a routing signal provided to the network to connect the incoming call to an agent station through the network. In the system disclosed in Gechter et al., when an incoming call is made to the call router, it decides which agent station should receive the call, establishes a call with that agent station, and then transfers the original call onto the second call to connect the incoming caller directly to the agent station and then drops out of the connection (See, Gechter et al., column 11, lines 45–51).
Other prior art call management, routing, and distribution techniques are disclosed in Andrews et al., U.S. Pat. No. 5,873,130, which is assigned to the assignee of the subject application. This patent discloses a communications system and method for automatically making telephone routing decisions with global authority based upon information gathered in real time from the entire communications system and global optimization criteria. The entirety of the disclosure of the Andrews et al. patent is incorporated herein by reference.
In conventional systems that implement the call processing techniques disclosed in the Andrews et al. patent, it is often desirable to facilitate certain “post-routing” call processing features. A call is considered to undergo “post-routing” processing when, after the call has already been initially routed to an initial destination, the same call is again processed such that another destination or called device becomes involved in the call. Examples of conventional “post-routing” call processing features include, e.g., the ability to transfer a call, initially routed via a public network (e.g., a public switched telephone network (PSTN)) to a first called device (e.g., an ACD and/or interactive voice response (IVR) unit-containing system), from the first called device to a second, remote called device, the ability to conference the calling device and/or the first called device with the second called device, etc. Such post-routing call processing may be initiated by the first called device, and when the called devices comprise ACD or IVR systems typically is facilitated by one or more telecommunications inter-site tie-lines connecting the first and second called devices. Unfortunately, however, the use of such inter-site tie lines undesirably increase the cost and complexity of implementing such post-routing call processing features.
Other prior art communications systems utilize conventional integrated services data network (ISDN) and American Telephone and Telegraph (AT&T) technologies to carry out such post-routing call processing features, without using such inter-site tie-lines. However, such prior art communications systems do not control public switched telephone network and local switch resources (e.g., in the called devices) as a single virtual switching resource when implementing such post-routing call processing features. Disadvantageously, this undesirably increases the cost and complexity associated with implementing such post-routing call processing features in such systems, and makes less efficient the use of the telecommunications resources of the called devices and the public network.
Thus, it would be desirable to eliminate the need to use such inter-site tie-lines to facilitate post-routing call processing features, and to provide a mechanism that reduces the cost and complexity associated with implementing post-routing call processing features and ensures that telecommunications resources of called devices and the public network are used more efficiently than in the prior art.